Most successful writers including Terry, all say the same thing - if you can't do any writing, read and if you can't get into reading, write. Just do one or the other. Anything at all and see how it goes
With Terry it's so obvious that he reads very widely and thoroughly and so it follows that the more input you work at, the easier the inspiration comes. Inspiration comes as it will and to a large extent other people can't give it to you - you have
to be enthralled and fascinated and only you can create that hunger for want of a better term. Experience helps to and oneo of the best ways to get that is to be around people a lot. observing and joining in occasionally. The best books are all about people and they weakness and pleasures and emotions. Possibly this is why you're now feeling restless in a job where you don't get enough socialising?
I'm probably saying it wrong, but it comes down to this - if you're looking for an original story then you can't really expect other people to provide one for you, because if you don't find it yourself, then you most likely aren't going to get too far with it?
Hope this helps a little